The invention relates to a passive, reusable hand-held pom-pom-like device that simulates a sparkler. The invention can be used for amusement or as a warning device.
Hand-held devices for visual amusement or warning are known in the art. Offen et al., U.S. Pat. No. 4,369,215, discloses a finger-held pom-pom that includes a number of glossy strips for catching and reflecting light. Sliva, U.S. Pat. No. 4,490,419, discloses a pom-pom having a number of plastic streamers attached to a stick-like handle for amusement. Uchytil, U.S. Pat. No. 4,055,840, discloses a warning device that includes a number of strips made of flexible reflective material attached to the end of a cylindrical flashlight that shines light onto the reflective strips.
While such prior art devices are somewhat amusing and attention grabbing, the use of flexible strips that reflect ambient light limits the usefulness of the devices. Reflective strips can do no more than reflect the ambient light. As an example, if the ambient light is sunlight, the reflective strips will reflect sunlight, i.e., white light. If the ambient light is an orange light, the reflective strips can only reflect the orange light. When used as safety devices, the reflected light is unfortunately easily mistaken for random reflections from, say, water or perhaps a discarded piece of metal.
One attempt at improving the visibility of a reflective device was adopted by Uchytil who incorporated a light source at the base of the reflecting strips. However, while locating a light source proximate to the strips improves the visibility of the reflected light, the light reflected will nonetheless look like the source light.
Another way to improve visibility of a reflective warning or amusement device is through the use of an active chemical reaction. Although amusement or safety devices that use pyrotechnic chemicals such as magnesium to produce a brilliant light display are highly visible, such active devices are potentially dangerous. Such active chemical devices are certainly not suitable for use by unattended children. Further, such devices frequently may be used but once, thus raising their cost.
SUMMARY OF THE INVENTION
The present invention is a passive, reusable hand-held pom-pom-like device that simulates a sparkler. The present invention is capable of producing a brilliant display of crisply separated colors from ambient light, including relatively low intensity ambient light.
Although the ambient light normally includes light of many wavelengths (i.e., many colors), reflective devices such as disclosed by Offen, Sliva, Uchytil are not capable of diffracting or refracting the ambient light into its component spectra and reproducing the colors therein. Such reflective devices have the advantage, however, of being inexpensive to produce in that reflective foil costs only about five cents per square foot. More expensive mechanically ruled diffraction gratings are known in the art and may be produced with approximately 14,000 lines per inch. Unlike reflecting materials, diffracting materials are capable of dividing ambient light into its component spectra and displaying a number of colors. However, the colors so produced may be indistinct, tend to smear together and do not attract attention very well.
What is needed is a passive, reusable hand-held visual amusement or warning device capable of producing a brilliant display of distinctly separated colors from ambient light. Such a display would be highly visible and would not easily be mistaken with random reflections of white light.
The present invention includes a number of flexible strips of light-diffracting foil attached, in a preferred embodiment, at one end to a handle. The strips are preferably cut from a sheet of metallized polyester and embossed with a diffractive pattern. Ambient light is diffracted from the upper and lower surfaces of the strips. Because of the high resolution available with holographic techniques, a preferred embodiment uses a holographically produced diffractive pattern. A holographically produced pattern embossed onto the foil may contain a diffractive feature comparable to gratings with about 5,000 to about 100,000 lines/inch. In a preferred embodiment, the holographically produced pattern is one of a diffraction grating having about 29,000 lines/inch.
Although holographically embossed foil is known in the art, its high cost compared to reflective foil has caused such material not to be experimented with in constructing amusement or warning devices. Holographically embossed foil costs 6 to 30 times as much as reflective foil, and in addition the holographer charges an origination fee of several thousand dollars.
Further, in the past, conventional wisdom was that flat holographically produced media were always displayed in a flat format, and curved holographically produced media were displayed in a curved format. In contrast, the present invention displays a flat holographically produced medium (i.e., the material embossed with a holographically produced diffractive pattern, originally created in a flat photoresist medium) in a curved format (the embossed strips are flexible and allowed to assume random curved shapes). The use of flat holographically produced foil strips in a curved display yields a truly surprising and startling visual result by vividly displaying colors that are crisply separated, even in low ambient light. The resultant device is more visible and more attention attracting than known passive devices.
Until the present invention, it was not known that the high resolution provided by holographically embossed foil streamers would produce vivid, brilliant color separation and eye-catching display. Similarly until the present invention it was not known that foil embossed with a holographically produced pattern of a planar grate could be displayed in a curved format to produce a sparkler-like visual display from a passive, reusable device that may be hand-held.
The visual effect produced by the present invention is surprising. A vivid dynamic display of crisply separated colors is produced as ambient light is diffracted by the foil strips. If the present invention is shaken or twirled or otherwise moved, the visual display becomes even more sparkling. The viewer's eye perceives a spectrum of brilliant colors which change as the viewer's eyes or the strips move. Because each strip is flexible and free to move in different orientations, a ray of ambient light striking two strips typically produces different colors from each strip because the light strikes each strip, and in fact each part of each strip, at different angles. As the strips are moved with the common handle, a sparkling, brilliant kaleidoscopic rainbow effect is achieved.
The present invention is produced by selecting a thin flexible embossable material, such as metallized polyester, embossed with holographically generated diffraction patterns. Alternatively, a mechanically ruled diffraction grating or diffractive material produced by other means could also be used if capable of producing visual effects similar to that produced by holographically generated diffraction gratings. The foil is slit into strips which, in a preferred embodiment, are taped at one end to a handle. The invention may be held in a user's hand and as the strips are moved about, either through motion of the user's hands or through their own motion, a sparkling kaleidoscopic visual display of brilliant colors is produced.
Applicant is not aware of commercially available amusement or warning devices made with strips of mechanically ruled diffracting patterns in a flexibly curved array. Experiments by applicant using mechanically ruled strips demonstrate that the intensity and color separation of light produced by the preferred embodiment of the present invention is substantially and significantly superior to what is produced by either reflective foils or the best mechanically reproduced diffracting patterns.
The present invention is especially useful under low light ambient condition because of the relative brilliance and crisp separation of the colors produced. The present invention is passive, safe and reusable and could, for example, be used as streamers on bicycle handlebars to improve visibility to motorists, especially in dim light. The present invention could be used as a signalling device for lost campers or downed airmen. Because the light diffracted from the present invention includes a spectrum of brilliant colors, the present invention is visibly more discernible and therefore effective than a warning device that merely reflects white or ambient light back at an observer. It is well known that colors and motion increase the visual impact upon an observer. Further, while objects in nature may reflect white light (a glittering rock or discarded piece of metal, for example), the brilliant colorful display produced by the present object is readily discernible from what might be produced by natural objects. A rescue aircraft, for example, would be more likely to observe and investigate the source of a rainbow display of colors than would be the case with a sighting of reflecting white light.
One advantage of the present invention is that a reusable, passive amusement or warning device is advantageously produced, capable of being hand-held and diffracting ambient light to produce a brilliant, sparkling kaleidoscopic display of colored light, to attract the attention of a viewer.